Device for registering the charging condition of airships



Patented Nov. 12, 1935 UNITED STATESPATENT OFFICE- DEVICE FOR REGISTERING THE CHARGING CONDITION OF AIRSHIPS Karl Stahl, Friedrichshafen, Germany, assignor 5 the carrying capacity.

to the fir'm Luftschifiliau Zeppelin Gesellschaft mit beschrtimkter Haftung, Friedrichshafen,

Germany Application June 28, 1920, Serial No. 392,613 In Germany August 7, 1916 14 Claims.

the observation of the gas-space with regard to.

its charging condition, which is so essential for As is well known, a balloon of sufiicient lifting power rises until it reaches the so-called pressure height, in which the originally slack gas envelope is completely filled with the gas and assumes its maximum volume. When exceeding the said height, a balloon with open appendix will. discharge gas until, when reaching the ceiling of buoyancy equilibrium, a state of equilibrium is produced. In a balloon with closed appendix, an excess pressure is produced in the gas-space with regard to the atmosphere, as soon as it exceeds its pressure height, which excess pressure, on reaching the ceiling of buoyancy equilibrium, as-

sumes its maximum value, unless the gas previously escapes through safety-valves. If, on account of variations in the air-pressure and temperature, the lifting power decreases, the balloon will sink and the lifting gas begins to contract; In a balloon with open appendix, air passes throughthe appendix from the outside into the gas-space, thereby contaminating its contents. For this reason, balloons with closed appendices and with safety valves are preferably used. In the latter case, .a. decrease of the gas volume, will result in a contraction of the, gas envelope, so that each fullness condition corresponds to a certain form of the cell.

In airships, which are mostly provided with single gas-cells, similar, but still more complicated conditions prevail. On the one hand, by means of the steering device, a certain dynamic upward or downward motion can be produced, whereas, on the other hand, losses of gas and ballast should, as far as possible, be avoided. For this reason, it is of great importance for the pilot to be constantly informed with regard to the fullness condition of the gas-cells. This can be efiected in such a manner that, for recording the fullness condition of airship-cells, the wall of the cell is connected with a device which whenever the wall of the cell becomesslack or the volume of the cell exceeds a certain limit, operates an electric signal. An electric signal is of special advantage, as it-will respond safely in the case of certain variations of form.

In the further development of the invention the device is connected with a pointer and scales, so as to insure a permanent control of the fullness condition, without having recourse to a number of contacts.

cell about half full of gas.

Fig. 2 is a longitudinal section of the rigid airship, corresponding to Fig. 1, on an enlarged scale.

Figs. 3 and 4 are views, partly in section, of the two recording devices.

The cell A, which is about half full of gas, rests '10 with its upper part against the frame B of the airship. Between the lowest point a of its slack bottom a and the lower part of the frame B, which carries a passage b, there is left a space within which a man may walk. At the bottom of the cell II at a, there is fixed a wire C, running over a number of guide pulleys D on the ceiling of the passage b toa depth indicator arranged in the pilot car F. In the form of the invention shown in Fig.

3 such a depth indicator consists of a weight E 20 attached to the wire and moving in a vertical guide e A scale e fixed to the guide e ,-serves to indicate the volume of the cell in its lowest position, which corresponds to the .taut condition of the cell the weight E closes a switch n of an N electric circuit, 0, thereby operating an alarm p. If, on account of a considerably vertical motion of part a of the-cell, the stroke of the depth indicator weight E should become too long, reducing devices may be employed, so as to keep the length of the scale c within practical limits. Instead of a weight, the wire C may be kept under tension by a spring. This is especially advisable if reducing devices are provided. At different points of the scale e electric contacts a: may be attached, which, on the passage of the depth indicator E will close the circuits 2 to signalling lamps g. If it should prove necessary, signals may be transmitted from either of the guide pulleys to different observers stations. Thus, a depth indicator may be arranged immediately below the cell which is to be supervised. The arrangement described is especially adapted for ascertaining the volume and consequently the conditions of the cell which is only partly full or has just become taut. On the other hand, it is less reliable, if the conditions .of a closed cell between the pressure-height and the ceiling is to be supervised, since the variations in the form or the displacement of the bottom of the cell, due to the increasing excess pressure in the cells, are comparatively small. In order to insure a connection with the wall of the cell, a plate has been provided, which acts upon the recording and signalling devices of the airship by means of rods. The transmission by means of the plate takes place only in the case of a com-= pletely full cell, when it permits of a careful supervision of its conditio The device, shown in the form of the invention according to Fig. 4 is provided with a plate G, which is so arranged in the lower part of the frame of the airship B that it is covered by the bottom a of the cell as soon as the cell has become nearly taut. The plate is under the action of a spring H by means of a transmission rod g the abutment h' of said spring being rigidly connected to the rod 9 which passes through said abutment. The lower abutment h, through which the rod 9 passes, rests against a hollow screw J, which can be displaced slidably through a spider b formed in a casing b rigidly connected to the frame B of the airship. In order to secure the upper part of the plate in its position a stop b has been provided. The lower part of the transmission rod g moves along a scale K which serves as a visible indicator of the excess pressure in the cell A. A case M provided in the lower part of the casing 27 is closed gas-tight by means of a packing m and an india rubber diaphragm r and is displaceable vertically. A switch s in the case opens and closes an electric circuit t, which, in the lower position of the plate G, is closed by means of the end of the transmission rod 9 so that, as soon as a predetermined excess pressure in the cell is produced, an alarm signal u, in the observers station, for instance in the pilot's car F, is operated.

As may be seen, the displacement of the plate G depends in the first place upon the size of the plate, the strength of the spring H and the excess pressure in the cell A. The weight of the part of the gas envelope resting on the plate, may be compensated by the spring. Thus a slight variation in the form of the gas cell, caused by variation of the pressure difference between the gas inside and the air outside of this portion of the gas cell may be indicated and measured before, during and after the. time the gas cell is subjected to the pressure variations occurring between pressure height and ceiling. It is not necessary to arrange the plate in the lowest part of the frame, since the excess pressure, existing in the taut cell, shows itself throughout the wall of the cell.

In addition to or instead of the electric transmission mechanism s and t a number of contacts a: in the circuit 2, which is the same-in both Figs. 3 and 4, may be arranged on the case M, so that signals 'at y for various steps of excess pressure may be given. Furthermore, by the provision of the transmission rod g a-continuous mechanical indication of the varying excess pressure is ensured. The devices described above may also be equipped with recording devices which permit of a subsequent control of the fullness conditions inthe single cells with regard to their temporal sequence.

I claim:

l. The combination with an airship havingan inflated gas cell therein, of an excess pressure indicator on said airship, and a yieldably mounted plate arranged exteriorly of the cell and operable by excessive pressure in the gas cell to actuate the indicator.

2. An aircraft having a gas holding compartment therein, automatic excess pressure responsive means associated with said compartment, a station remote from said means and electrically operated means at said station connected with said first mentioned means for in- .dicating the excess pressure in said compartment.

3. An aircraft having a gas holding compartment therein, said compartment including a l movable portion, a member depending from said portion and automatically responsive to movement of said portion, a station remote from said member and electrically operated means at said station co-operating with said member for in- 1Q dicating when said compartment reaches its maximum volume.

4. An air craft having a gas holding compartment therein, said compartment including a movable lower Portion, a member arranged exteriorly 15 of said portion so as to be responsive to movement either upwardly or downwardly of said portion, a stationremote from said member, and electrically operated means at said station cooperating with said member for indicating when 20 the compartment is full of gas.

5. An air craft having a gas holding compartment therein, excess pressure responsive means associated with said compartment, a station, and means at said station connected with said first as mentioned means for indicating the excess pressure in said compartment.

6. An aircraft having a gas holding compartment therein, said compartment including a movable lower portion, a member secured to and arranged exteriorly of said portion so as to be responsive to movement either upwardly or downwardly of said portion, a station, and means at said station cooperating with said member for indicating when said compartment reaches its maximum volume.

7. An air craft having a gas holding compartment therein, said compartment including a movable lower portion, a member depending from and responsive to movement either upwardly or 40 downwardly of said portion, a station, and means at said station cooperating with said member for indicating the movements of said member to thereby determine when the compartment is full of gas.

6. An air craft having a gas holding compartment therein, said compartment including a movable lower portion, automatic mechanism connected with and located exteriorly of said compartment and responsive to movement either upso wardly or downwardly of said portion for indicating when the compartmentis full, 9. station remote from said mechanism, and electrically operated means at said station cooperating with said mechanism for indicating the movement of 66 said mechanism.

9. An airship having a rigid frame, an expansible and contractible gas cell which, under different conditions, partially or wholly fills the frame, an observing station, an indicator at said 00 station, means connecting said cell and said indicator for showing the position of the lower portion of said-cell, means including a second indicator at said station, and means operated by the cell after it fills the frame for operating the 65 second indicator to show the difi'erence between atmospheric pressure and the pressure in said cell at least adjacent said last named means.

10. An airship having a rigid frame, a gas cell inserted in the frame and having a lower portion movable in response to changes in volume of the gas in the cell, an observing station, an indicator at said station for indicating when the cell is full, 9, device depending from the lower portion of said cell and responsive to movements of said lower portion, and means connecting said device with said indicator.

11. An airship having a rigid frame provided with a passageway in the lower part thereof, a

5 gas cell inserted in the frame and having a lower portion movable in response to changes in vol-' ume of the gas in the cell, an observing station,

an indicator at said station for indicating when the gas cell is .full, mechanism in the passagew way connected to the lower portion of said cell and responsive to movements of said lower por-' tion, and means connecting said mechanism with said indicator.

12. An airship having a rigid frame, a gas cell 5 inserted in the frame and having a lower portion movable in response to changes in volume of the gas in the cell, an observing station, an

electrically energized indicator at said station for indicating when the cell. is full, mechanism 20 arranged exteriorly of and depending from the lower portion of said cell and responsive to movements of said lower portion, and means includ-.

'ing an electric circuit connecting said mechanism with said indicator.

13. An airship having a rigid frame, an expansible and contractible gas cell which, under different conditions, partially or wholly fills the 5 frame, an observing station, an indicator at said station, and -means operated by the cell after it fills the frame for operating the indicator to show the difference between atmospheric pressure and the pressure in said cell at least adjacent 10 said means.

14. An airship having a rigid frame, an ex- .pansible and contractible gas cell which, under different conditions, partially or wholly fills the frame, an observing station, an electrically op- 15 era'ted indicator at said station, and means operated by the cell after it fills the frame and including an electric circuit for operating the indicator to show the'difierence between atmospheric pressure and the pressure in said cell 20 at least adjacent said means.

KARL STAHL. 

